The purpose of this study is to demonstrate the long-term safety and efficacy (effect on growth of Prolease hGH given in the treatment of growth failure in children with Growth Hormone Deficiency. ProLease hGH is an experimental drug which is intended as a sustained release formulation of human recombinant growth hormone (somatropin; Genentech, Inc). This study is an extension study of Protocol ALK03-004 "A Phase III Multicenter, Open-Label Study of the Safety and Efficacy of ProLease hGH Administered in Children with Growth Failure Due to Growth Hormone Deficiency."